### Please describe the problem.

On Windows only the git annex repair command reports an error.

### What steps will reproduce the problem?

Following are the minimum steps to reproduce the problem. The problem occurs with any number of files in the repository. The --force option does not correct the problem. The problem does not occur on Linux or macOS.

[[!format sh """
mkdir repair-ambiguous-argument-bug
pushd repair-ambiguous-argument-bug
git init
git annex init
git annex repair
popd
"""]]

### What version of git-annex are you using? On what operating system?

git-annex version: 10.20230330-g98a3ba0ea5

git version 2.40.0.windows.1

Microsoft Windows [Version 10.0.19045.2846]

### Please provide any additional information below.

[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log

repair Running git fsck ...
Fsck found no problems. Checking for broken branches.
fatal: ambiguous argument 'refs\heads\master': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
fatal: ambiguous argument 'refs\heads\git-annex': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
fatal: ambiguous argument 'refs\heads\adjusted\master(unlocked)': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
fatal: ambiguous argument 'refs\basis\adjusted\master(unlocked)': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
Found problems, attempting repair.
fatal: ambiguous argument 'refs\heads\master': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
fatal: ambiguous argument 'refs\heads\git-annex': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
fatal: ambiguous argument 'refs\heads\adjusted\master(unlocked)': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
fatal: ambiguous argument 'refs\basis\adjusted\master(unlocked)': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
Some git branches refer to missing objects:
        refs\heads\master
        refs\heads\git-annex
        refs\heads\adjusted\master(unlocked)
        refs\basis\adjusted\master(unlocked)
To force a recovery to a usable state, retry with the --force parameter.
failed
repair: 1 failed

# End of transcript or log.
"""]]

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

Yes. I am developing the easy-git-annex API for git-annex.

> Should be [[fixed|done]] now... It was reading the contents of the refs/
> directory recursively, and treating those names as refs, which is wrong
> on Windows due to path separator being different. --[[Joey]]
